Well, in that case, you could just set focus on the container element. That, or you could automatically generate a focusable element at the top of every slide that's hidden from the UI. 

Aria tabs might be a good option, since these are basically just tabs that auto-rotate. Speaking of, they do have a page on patterns and [http://www.w3.org/TR/2010/WD-wai-aria-practices-20100916/#tabpanel](a Tab Panel is one of them). In that, [http://codetalks.org/source/widgets/tabpanel/tabpanel1.html](focus always stays on the tab/link), and then to get to the content the user just presses tab. 

For this instance, that would require re-ordering the HTML to have the links first. That'll take some effort to get done (flex-box, I wish you could help out already...).